1. Field of the Invention
The present invention relates to an image forming apparatus, a control method therefor, and a storage medium storing a program for executing the control method.
2. Description of the Related Art
Some image forming apparatuses such as printers, facsimile machines, and multi-function peripherals have a push scan function and a pull scan function. An operation setting of the push scan function is set through an operation unit of an image forming apparatus, and an operation setting of the pull scan function is set through an operation unit of an external device (hereinafter, referred to as the external operation unit). When the operation setting of the push or pull scan function is made, the image forming apparatus receives an operation setting request, scans an original to generate image data, and transmits the image data to the external device.
Recently, portable terminals such as smart phones and tablet PCs have been in widespread use that are excellent in operability, response, and/or visibility. In the field of image formation, attempts have been made to use portable terminals as external operation units for image forming apparatuses. For example, to improve the user-friendliness, there are attempts to simplify the operation setting to the image forming apparatus by using intuitive operation such as gesture input performed via a touch panel of the portable terminal and to display an image in detail by using excellent visibility of the portable terminal.
In an operation environment where an image forming apparatus can be operated from portable terminals of plural users, there is a possibility that the image forming apparatus successively receives operation setting requests from the operation unit of the image forming apparatus and/or the portable terminals. This can cause a problem. In a case, for example, that the operation setting of the push scan function is set through the operation unit of the image forming apparatus and the image forming apparatus receives an operation setting request of pull scan function from one of the portable terminals (external devices), there is a fear that an image of an original of a user utilizing the push scan function is delivered to another user utilizing the pull scan function.
Japanese Laid-open Patent Publication No. 2004-215009 discloses an image data transmission system in which when the operation setting of push scan function is set through an operation unit of an image forming apparatus (MFP), control is made to refuse to receive an operation setting request from an external device, thereby preventing an image of original of a user utilizing the push scan function from being delivered to a third party utilizing the pull scan function.
However, with the above-described exclusive control where the operation setting request from the external device is refused to be received when the operation setting is made through the operation unit of the image forming apparatus, the operation setting request of pull scan function from the external device is refused until completion of a push scan operation of the image forming apparatus. As a result, the user who has made the operation setting request from the external device is obliged to wait for a long time, and there is a possibility that the pull scan function whose operation setting is first set from the external device is executed after execution of the pull scan function whose operation setting is subsequently set through the operation unit of the image forming apparatus.
In both the case of executing the push scan function and the case of executing the pull scan function, an ADF (auto document feeder) of the image forming apparatus is used. In other words, a resource conflict occurs in the image forming apparatus. The above-described exclusive control must be made in this case. However, if the exclusive control is performed when a resource conflict does not occur, the operating rate of the image forming apparatus is lowered.